The objectives of this research include the study by physical and chemical methods of the non-covalent interactions of macromolecules. Studies on geometry and mechanisms of self-assembly of oligomeric proteins and fibrin illustrate systems which serve as models. We continue our emphasis on studies on the metabolism and molecular structure of human serum lipoproteins. Consistent with these goals is continuing research on the development of experimental techniques which are an aid in such studies, particularly in the area or ultracentrifugation and electron microscopy.